Method of improving paper machine operation



Patented June 2, 1931 UNIT STATES,

v PATENT OFFICE HAROLD ROBERT RAFTON, OF'LAWRENCE, MASSACHUSETTS, ASSIGNOR '10 RAIFOLD PROCESS CORPORATION, A CORPORATION OF MASSACHUSETTS METHODOP IMPROVING PAPER MACHINE OPERATION No Drawing. Application filed December 11, 1928, Serial No. 325,407. Renewed March 5, 1981'.

This invention relates to the manufacture of paper, more particularly to the manufacture of paper filled with alkaline filler.

, The principal object of my invention is to provide a method for paper manufacture whereby furnishes containing alkaline filler may be run on the paper machine substantially free from soft lumps.

An important ob'ect of my invention is to provide av method whereby both alkaline filler and casein may be used in the same furnish substantially without difficulty from soft lump formation.

A further. object is to provide a method whereby coated Fbroke in, which alkaline filler has been used as a coating constituent I and casein as an adhesive may be used in a beater furnish; V

A further object of my invention is to produce paper containing casein and alkaline filler in the furnish, which is substantially free from lumps and lump spots.

Other objects and advantages of my in- 'vention will become apparent during the course of the following description. In the manufacture of substantially un-. sized paper filled with alkaline filler, particularly when old paper stock is one of the fibrous constituents, soft lumps form in the furnish and cause breaks on the paper machine. I- have found that this formation of lumps is. traceable 'to the presencein the furnish of casein from coated broke, and that the trouble from soft lumps may be substantially eliminated in the manufacture of paper filled with alkaline filler by substantially excluding casein from the furnish.

or desirable.

I havenow discovered a method whereby the manufactureof paper filled with alka-.

' directly to the furnish. I

material, casein, and alkaline filler.

However this exclusion is not always feasible trimmings, or the like) in the furnish, or from the. old paper stock made" from old papers possessing some casein bearing constituents, or from circulating mill waters which in turn originally derive their casein from such sources, or even from casein added The method I employ is similar to that which I disclose in my copending applications Serial Nos. 304,171], and 304,174, both filed September 5, 1928, for the elimination of foam in paper manufacture. -My method in its preferred embodiment consists in the addition of alum preferably continuously and preferably in solution at the wet end of the paper machine toa mix including fibrous There may also be present the mix size, for example rosin size, in an amount of itself insufficient to impart a substantial degree of sizing to the paper if a substantially un'sized paper is to be manufactured, or in a greater amount if a sized paper is to be manufac-v tured, and this size may or ma not have been 75 previously precipitated in the eater by a size precipitant, such as alum. In the case where. alum is originally added to the size in the relatively concentrated mix the action ofthe alum at the wet-end of the paper machine on the size-alum precipitate originally formedis a restorative one. "When the size is used without-preliminary precipitation-suck by Y alum, theaddition of alum at the wet en of the paper machine acts as a precipitant.

An illustrative furnish which may be satisfactorily used in carrying out my inventlon -Mateiials added in beater i Pounds Fibrous furnish, e. g. sulphite pulp and soda pulp, equal parts (air dry weight) 1400 Casein containing ingredient (air dry weight) e. g. coated broke Alkaline-filler (bone dry weight), e. g.

calcium carbonate magnesium hydroxi Material added proportionately and cow tinuously on dilution Pounds Material added proportionately and contimtouslg on dilution P ounds Alum 60 Another furnish which may be used is:

' Materials added in beater Pounds Fibrous furnish, e. sulphite pulp, -soda pulp and old pa r stock, equal parts (air dry weight iin; asein containing ingredient (air dry weight) e. g. coated broke;

Rosin size Alum moo

Alkaline filler (bone dry weight), e. g.

I complete destruction. I thus add the alum calcium carbonate magnesium hy-.

droxide 300 Material added proportionately and cone timtously on dilution P d Olin S Alum 90 alum is added tothe stock in concentrated form, and particularly when the concentrated stock is subjected to agitation as is normal P in stuff chests, that the effect of the alum is speedily deteriorated, even to the point of at a point where there is a minimum of intimacy and time of contact'of the constituents of the mix, i. e., at the wet end of the paper machine. I have found that agitation even in the dilute state gradually deteriorates-the effect of the alum, but as a practical proposition the time that the alum is in contact with the stock in the dilute state prior to its delivery to a web-forming device is insufficient to permit a substantial deterioration of its beneficial action. f

The furnishes given above are to be considered as illustrative only and not limiting, as I have found that I may carry on my-invention with a wide variety of materials used in widely varying quantities and still obtain satisfactory results.

The papers made by my process may be finished as usual as by machine calcndering or supercalendering if desired, and if-sized, may be used for'conversion, e. g. forcoating.

My method is particularly valuable as 1t permits the operation of a mill. manufacturing both coated paper and alkaline*fille l paper without thesegregation of the coated broke into furnishes which do not contain alkaline filler. It also does away substantially with the difficulties and necessity of .isolating casein bearing ingredients, from alkaline filler furnishes.

It also provides a broke from paper which has been coated means. whereby the with alkaline filler. as a coating material and casein as adhesive maybe directly used in furnishes containing either alkaline filler, or other filler such as clay, without causing difficulty onthe paper machine.

As will be apparent to one skilled in the art this is of very considerable importance and results in very material economy and simplification of operation particularly in mills in which alkaline filler is used either as a coating constituent or as a filler or both.

of aluminum such as the chloride or the like. I

Because of economy, however, I prefer to use ordinary alum.

In'place of rosin size I may use other sizes, such as soaps, for example, the oleates, or any other material derived bytreatment with an alkaline substance or the like from material originally of'acid characteristics 'or from material which likewise is of a partly'or completely saponifiable nature such for example as saponified beeswax. I may also use other sizing materials such as paraffin emulsions, for example as set forth in my copendmg aplications Serial Nos. 304,170, 304,173, 304,176 and 304,17 7, all filed September 5, 1928.

Where I use the term alkaline filler, I mean substantially water insoluble filler which when agitated-in contact with freshly boiled distilled water. say for an hour, will impart a pH value to such water greater than 7.0, that is, which will be on the alkalineside of the neutral point. Among the fillers included in this group may be mentioned calcium carbonate, of which lime mud from the causticizing process is one form; calcium carbonate magnesium basic carbonate employed in the paper disclosed in my U. S. Patent No. 1,595,416, issued August 10, 1926; calcium carbon ate magnesium hydroxide disclosed in my U. S. Patent No. 1,415,891, issued May 9, 1922; and other substantially water insoluble normal or basic carbonates of alkaline earth metals (which expression is herein intended to include magnesium), or

, compounds, doublesalts, or physically associated mixtures of these with one or more other acid soluble materials ofa substantially water insoluble nature.

By the term alkaline filler I also intend .to include fibrousmate'rial and/or other ma"- terial such as paper coatingconstitnents or the like containingpne or more compounds ofthe character referred to, such as old papers or similar piipers, broke, or the like.

When I use the word paper herein, I use .it in the broad sense to include products of manufacture of all types and of all Weights and thicknesses, which contain ,as-an essential constituent a considerable amount of pre pared fibre and which are capable of being produced ona Fourdrinier, cylinder, or other forming, felting, shaping or molding machine. D I

' By the term wet end of the paper'machine I intend to include those instrumen- .talities employed in paper manufacture by which and/or in which a relatively concentrated-paper mix is diluted, and treated, c0nveyed or fed up to the point of web-formation such as the mixingbox, regulating and proportioning .devices, rifiiers,- trougl is,

screens, head boxes, inlets, and the like, in-

, fermented or decomposed which settle or form on chest and pipe surfaces, and when dislodged work through the screens and on to the wire. Of course, slime also forms in the head-box and ,inletsafter the machine has run for a relatively long period of time without wash-up, but the soft lumps I 'de-' scribe are entirely distinct therefrom and form, and start to give trouble, even within as short a time as several hours after the cleaned,

Where I use the word .casein? herein, 1 use it in the generic sense to include casein and /or compounds or derivatives thereof.

. While I have described in detail the preferred embodiment of my inventon,.it is to be understood that the details of procedure, the proportions'of ingredients, and the arrangement of steps may be widely varied without departing from the spirit of my invention or the scope of the s'ubjoined. claims.

I claim: v

1. The method of manufacturing 'paper filled with alkaline filler and containing casein in its furnish, comprising adding to a fibrous mix comprising fibrous material,

head-box and inlet have been thoroughly fib casein bearing constituent, and alkaline filler, alum under conditions favoring the mimmizing of time of contact of the constituents f of the mix, and thereafter making paper therefrom. V

2, The method. of. manufacturing paper filled with alkaline filler and containing" casein in its furnish, comprising adding to-a fibrous mix comprising fibrous material,

casein bearing constituent, and alkaline filler, alum under conditions favoring the minimizingof intimacy and timeof contact of' I the constituents of the mix, and thereafter making paper therefrom.

I 3. The method of manufacturing paper "filled with alkaline filler -and contaimng casein in its furnish, comprising adding to a fibrous mix comprising fibrous material,

casein bearing constit'uent, and alkaline filler, alum at the wet end of.the paper machine,

and thereafter making paper therefrom.

4. The method of manufacturing paper filled with alkaline filler and containing casein in its furnish, comprising adding to a fibrous. mix comprising fibrous material, casein bearing constituent, and alkaline filler, a salt of aluminum at the wet end of the paper machine, and thereafter making paper machine, and thereafter making paper therefrom.

' 6. The method of manufacturing paper filled with alkaline filler and containing casein in its furnish, comprising adding to a fibrous mixcomprislng fibrousmaterial,

' casein bearing constituent, and alkaline filler, acidic material at the wet end of the paper.

machine, and thereafter making paper therefrom.

7. The method of manufacturing paper filled with alkaline filler and containing casein in its furnish, comprising adding to a eluding old paper stock, casein bearing constituent, and'alkaline filler, alum at the wet .end of the paper machine, and thereafter making paper therefrom.

8, The method of manufacturing paper filled with alkaline'filler and containing casein -in its furnish, comprising adding to a fibrous mix comprising fibrous material including sulphite pulp and soda pulp and old rous mix comprising fibrous material inin in its furnish, comprising adding to a old paper stock, casein bearing constituent comprising coated broke, and alkaline filler,

alum at the wet end of the paper machine, and thereafter making paper therefrom.

11. The method of manufacturing paper filled with alkaline filler and containing casein in its furnish, comprising adding to a fibrous mix comprising fibrous material, casein bearing constituent, and alkaline filler comprising alkaline earth metal compound, alum m at the wet end of the paper machine, and

thereafter making pa er therefrom.

12. The method 0 manufacturing paper filled with alkaline filler and containing casein in its furnish, comprising adding to a.

fibrous mix comprising fibrous material, case in bearing constituent, and alkaline filler comprising calcium carbonate, alumatthe wet end of the paper machine, and thereafter making paper therefrom. i

13. The method of manufacturing paper filled with alkaline filler and containing casein in its. furnish, comprising adding to a fibrous mix comprising fibrous material, case- -in bearing constituent, and alkaline filler comprising calcium carbonate and magnesium compound, alum at the wet end of the paper Enachine, and thereafter making paper thererom.

14. The method of manufacturing paper filled with alkaline filler and containing casein in its furnish, comprising adding to a .fibrous mix comprising fibrous material, casein bearing constituent, and alkaline filler comprising calcium carbonate magnesium hydroxide, alum at the wet end of the paper machine, and thereafter making paper therefrom.

15. Themethojdof manufacturing paper filled with alkaline filler and containing casefibrous mix comprising brous material, casein bearing -constituent, size, and alkaline filler, alum at the wet end of the paper machine, and' thereafter making paper therefrom. p

16. The method of manufacturing paper filled with alkaline filler and containing casein in its furnish, comprising addingto a fibrous mix comprising fibrous material, casein bearing constituent, the reaction product of size and alum affected by alkaline filler, an alkaline filler, alum at the wet end of the papermachine, and thereafter making paper therefronn a 17-. The method of manufacturing paper in in its furnish,'com rising adding to a filled with alkaline filler and containing casein in its furnish, comprising adding to a fibrous mix comprising fibrous material, casein bearing constituent, size in an amount insufiicient to produce a substantial degree of sizing in the paper, and'alkaline filler, alum at the wet end of the paper machine, and

thereafter making paper therefrom.

18. That step in a method of manufacturing pap'er filled with alkaline filler and containing casein in its furnish, comprising add- I ing alum to the paper mix at the wet end of the paper machine.

' 19. A papermaking mix ready for delivery to a'web-forming device, and capable of running on the paper machine substantially without difliculty from soft lumps, comprising fibrous material, casein bearing constituent, alkaline filler, and alum substantially undeteriorated by said alkaline filler.

20. A papermaking mix ready for delivery to a web-forming device, and capable of run- 4 ning on the paper machine substantially without difliculty. from soft lumps, comprising fibrous material including old paper stock and coated broke, alkalinefiller, and alum substantially undeteriorated bysaid alkaline filler.

21. A paper substantially free from soft lumps, comprising ingredients comprising fibrous material, casein bearing constituent,

alkaline filler, and aluminum compound.

22. A paper substantially free from soft lumps, comprising papermaking ingredients comprising fibrous material including old paper stock and coated broke, alkaline-filler, and an aluminum compound.

23. A paper substantially free from soft fibrous material, casein'bearing constituent, alkaline filler, sizing, and aluminum compound.-

24. A paper substantially free from soft" lumps, comprising ingredients comprising fibrous material, casemzbearing constituent, alkallne filler, slzing 1n an amount msuflicient to impart a substantial degree of sizing to the paper, and aluminum compound. In testimony whereof I aflix my signature.

HAROLD ROBERT RAFTON.

.lumps, comprising ingredients comprising 

